1. Field of the Invention
This invention relates to a temperature monitoring apparatus for microprocessors, having a fan device for producing an air stream for cooling the microprocessor. The inventive temperature monitoring apparatus can, additionally be used for desk top personal computers, or similar, or similar temperature-sensitive apparatus.
2. The Prior Art
Temperature monitoring apparatus for sensing the temperature of electrical components are known in the prior art. However, known temperature monitoring apparatus failures altogether have the disadvantage that due to overheating cannot be effectively prevented. An object of the invention is therefore to provide a temperature monitoring apparatus which can effectively prevent overheating of a microprocessor.
In these type of temperature monitoring apparatus, the temperature of the microprocessor is sensed by means of a heat probe mounted in the area of its surface. A regulator circuit is provided for increasing the speed of the fan device when the temperature rises, and decreasing it at falling temperature, based on the temperature sensed by the heat probe. A speed monitoring device is also provided for monitoring a presettable speed range of the fan device, and emits a warning signal in cooperation with an electronic circuit, in order to notify the user of an apparatus, operated with the microprocessor to manually switch off the same when the preset speed range of the fan device is exceeded.
In the inventive temperature monitoring apparatus, the temperature of the microprocessor is to be sensed by means of a heat probe mounted in the area of its surface. A regulator circuit is also provided for increasing the speed of the fan at rising temperatures, and decreasing it at falling temperatures depending upon the temperature sensed by the heat probe. A speed monitoring device is also provided for monitoring a presettable speed range of the fan, and emits a warning signal in cooperation with an electronic circuit in order to ask a user of an apparatus operated with the microprocessor to manually switch off the same when the present speed range of the fan device is exceeded. It is possible to provide an apparatus having a further monitoring device which can reliably avoid overheating of the microprocessor in case sufficient cooling cannot be ensured by means of the regulator alone, for example upon nonfunctioning or poor functioning of the fan.
In a first preferred embodiment of the inventive apparatus, the heat probe sensing the temperature of the microprocessor is disposed in a bore formed in the bottom of a heat sink of the microprocessor. The fan device is preferably disposed on the heat sink of the microprocessor.
In another preferred embodiment of the inventive apparatus, the speed monitoring device for monitoring a presettable speed range of the fan contains a device that delivers a stroboscope signal clocked with the rotational frequency of the fan and contains a device clocked with a preset frequency for evaluating the stroboscope signal.
In still a further preferred embodiment of the inventive apparatus, the fan is dimensioned so as to be able to deliver an air quantity of about 80 cubic meters per hour.
The heat probe of the inventive apparatus is preferably formed as an NTC thermistor.
In accordance with a further preferred embodiment of the inventive apparatus, the heat probe is formed alternatively as an NTC resistor that acts functionally as a regulator circuit.